<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>更新时的一个问题</title>
    <!-- 引入Vue -->
    <script type="text/javascript" src="../js/vue.js"></script>

</head>
<body>

    <!-- 准备好一个容器 -->
    <div id="root">
        <!-- 遍历数组 -->
        <h2>人员列表</h2>
        <button @click="updateMei">更新马冬梅的信息</button>
        <ul>
            <li v-for="(person,index) in persons" :key="person.id">
                {{person.name}} - {{person.age}} - {{person.sex}}
            </li>
        </ul>

       
    </div>

</body>
    <script type="text/javascript">
        
        //用计算属性实现
        const vm = new Vue({
            el:'#root',
            data:{
                persons:[
                    {id:'001',name:'马冬梅',age:30, sex:'女'},
                    {id:'002',name:'周冬雨',age:20, sex:'女'},
                    {id:'003',name:'周杰伦',age:21, sex:'男'},
                    {id:'004',name:'温兆伦',age:18, sex:'男'}
                ],  
                
            },
            methods: {
                updateMei(){
                    // this.persons[0].name='马老师';
                    // this.persons[0].age=28;
                    // this.persons[0].sex='男';

                    this.persons[0] = {id:'001',name:'马老师',age:50,sex:'男'}    //无效
                    this.persons.splice(0,1,{id:'001',name:'马老师',age:50,sex:'男'})
                }
            },
        })  

    </script>

</html>